1 /*
2  * Copyright (c) 2021 Omar Polo <op@omarpolo.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #ifndef KAMID_H
18 #define KAMID_H
19 
20 #include "compat.h"
21 
22 #include <limits.h>
23 #include <stdint.h>
24 #include <tls.h>
25 
26 /* TODO: make these customizable */
27 #define KD_CONF_FILE		"/etc/kamid.conf"
28 #define KD_USER			"_kamid"
29 #define KD_SOCKET		"/var/run/kamid.sock"
30 
31 #define IMSG_DATA_SIZE(imsg)	((imsg).hdr.len - IMSG_HEADER_SIZE)
32 
33 #define MIN(a, b) ((a) < (b) ? (a) : (b))
34 
35 struct imsgev {
36 	struct imsgbuf	 ibuf;
37 	void		(*handler)(int, short, void *);
38 	struct event	 ev;
39 	short		 events;
40 };
41 
42 enum imsg_type {
43 	IMSG_NONE,
44 	IMSG_CTL_LOG_VERBOSE,
45 	IMSG_CTL_RELOAD,
46 	IMSG_CONTROLFD,
47 	IMSG_STARTUP,
48 	IMSG_RECONF_CONF,
49 	IMSG_RECONF_PKI,
50 	IMSG_RECONF_PKI_CERT,
51 	IMSG_RECONF_PKI_KEY,
52 	IMSG_RECONF_LISTEN,
53 	IMSG_RECONF_END,
54 	IMSG_AUTH,
55 	IMSG_AUTH_DIR,
56 	IMSG_AUTH_TLS,
57 	IMSG_CONN_GONE,
58 	IMSG_BUF,
59 	IMSG_MSIZE,
60 	IMSG_CLOSE,
61 };
62 
63 struct kd_options_conf {
64 	/* ... */
65 };
66 
67 enum table_type {
68 	T_NONE		= 0,
69 	T_HASH		= 0x01,
70 };
71 
72 struct table {
73 	char			 t_name[LINE_MAX];
74 	enum table_type		 t_type;
75 	char			 t_path[PATH_MAX];
76 	void			*t_handle;
77 	struct table_backend	*t_backend;
78 };
79 
80 struct table_backend {
81 	const char	*name;
82 	int		(*open)(struct table *);
83 	int		(*add)(struct table *, const char *, const char *);
84 	int		(*lookup)(struct table *, const char *, char **);
85 	void		(*close)(struct table *);
86 };
87 
88 /* table_static.c */
89 extern struct table_backend table_static;
90 
91 #define L_NONE	0x0
92 #define L_TLS	0x1
93 struct kd_listen_conf {
94 	STAILQ_ENTRY(kd_listen_conf)	 entry;
95 	uint32_t			 id;
96 	uint32_t			 flags;
97 	int				 fd;
98 	char				 iface[LINE_MAX];
99 	uint16_t			 port;
100 
101 	/* certificate hash => (virtual) user */
102 	struct table			*auth_table;
103 
104 	/* virtual user => local user */
105 	struct table			*virtual_table;
106 
107 	/* (virtual) user => export directory */
108 	struct table			*userdata_table;
109 
110 	char				 pki[LINE_MAX];
111 	struct event			 ev;
112 	struct tls			*ctx;
113 };
114 
115 struct kd_pki_conf {
116 	STAILQ_ENTRY(kd_pki_conf)	 entry;
117 	char				 name[LINE_MAX];
118 	uint8_t				*cert;
119 	size_t				 certlen;
120 	uint8_t				*key;
121 	size_t				 keylen;
122 	struct tls_config		*tlsconf;
123 };
124 
125 struct kd_tables_conf {
126 	STAILQ_ENTRY(kd_tables_conf)	 entry;
127 	struct table			*table;
128 };
129 
130 struct kd_conf {
131 	struct kd_options_conf					 kd_options;
132 	STAILQ_HEAD(kd_pki_conf_head, kd_pki_conf)		 pki_head;
133 	STAILQ_HEAD(kd_tables_conf_head, kd_tables_conf)	 table_head;
134 	STAILQ_HEAD(kd_listen_conf_head, kd_listen_conf)	 listen_head;
135 };
136 
137 struct kd_auth_req {
138 	uint32_t	listen_id;
139 	char		hash[128+1];
140 };
141 
142 /*
143  * 9p message header.
144  *
145  * The message itself is len bytes long (counting the whole header
146  * too.)
147  */
148 struct np_msg_header {
149 	uint32_t	len;
150 	uint8_t		type;
151 	uint16_t	tag;
152 };
153 
154 struct qid {
155 	uint64_t		 path;
156 	uint32_t		 vers;
157 	uint8_t			 type;
158 };
159 
160 /* useful constants */
161 #define HEADERSIZE	(4 + 1 + 2)
162 #define	VERSION9P	"9P2000"
163 #define MSIZE9P		((uint32_t)4*1024*1024)
164 #define NOTAG		((uint16_t)~0U)
165 #define NOFID		((uint32_t)~0U)
166 #define NOUID		(-1)
167 #define QIDSIZE		13
168 #define MAXWELEM	16
169 
170 #define NPSTATSIZ(namlen, uidnam, gidnam, unam) \
171 	(6 + QIDSIZE + 20 + 2 + namlen + 2 + uidnam + 2 + gidnam + 2 + unam)
172 
173 /* bits in Qid.type */
174 #define QTDIR		0x80		/* type bit for directories */
175 #define QTAPPEND	0x40		/* type bit for append only files */
176 #define QTEXCL		0x20		/* type bit for exclusive use files */
177 #define QTMOUNT		0x10		/* type bit for mounted channel */
178 #define QTAUTH		0x08		/* type bit for authentication file */
179 #define QTTMP		0x04		/* type bit for non-backed-up file */
180 #define QTSYMLINK	0x02		/* type bit for symbolic link */
181 #define QTFILE		0x00		/* type bits for plain file */
182 
183 /* Topen mode/flags */
184 #define KOREAD		0x00
185 #define KOWRITE		0x01
186 #define KORDWR		0x02
187 #define KOEXEC		0x03
188 #define KOTRUNC		0x10
189 #define KORCLOSE	0x40
190 
191 /* 9p message types */
192 enum {
193 	Treaddir =	40,	/* .L */
194 	Rreaddir,
195 
196 	Tversion =	100,
197 	Rversion,
198 	Tauth =		102,
199 	Rauth,
200 	Tattach =	104,
201 	Rattach,
202 	Terror =	106,	/* illegal */
203 	Rerror,
204 	Tflush =	108,
205 	Rflush,
206 	Twalk =		110,
207 	Rwalk,
208 	Topen =		112,
209 	Ropen,
210 	Tcreate =	114,
211 	Rcreate,
212 	Tread =		116,
213 	Rread,
214 	Twrite =	118,
215 	Rwrite,
216 	Tclunk =	120,
217 	Rclunk,
218 	Tremove =	122,
219 	Rremove,
220 	Tstat =		124,
221 	Rstat,
222 	Twstat =	126,
223 	Rwstat,
224 	Tmax,
225 
226 	/*
227 	 * plan9ports' include/fcall.h also has a
228 	 *
229 	 *	Topenfd = 98,
230 	 *	Ropenfd,
231 	 *
232 	 * which it's not mentioned in the 9p "rfc" over at
233 	 * 9p.cat-v.org.  Ignoring that for now.
234 	 */
235 };
236 
237 /* kamid.c */
238 extern int verbose;
239 int	main_imsg_compose_listener(int, int, uint32_t, const void *, uint16_t);
240 void	merge_config(struct kd_conf *, struct kd_conf *);
241 
242 struct kd_conf	*config_new_empty(void);
243 void		 config_clear(struct kd_conf *);
244 
245 /* parse.y */
246 struct kd_conf	*parse_config(const char *);
247 int		 cmdline_symset(char *);
248 
249 #endif